Runhan Ye Universitat de Barcelona   Facultat d'Economia i Empresa Av. Diagonal 690 Barcelona, Barcelona 08034 Spain   ryeyexxx69@alumnes.ub.edu             JEL Areas: E2 : Macroeconomics: Consumption, Saving, Production, Employment, and Investment: General (includes Measurement and Data) J6 : Mobility, Unemployment, and Vacancies: General